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mfem/fem/bilinearform_ext.cpp
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2019-06-09 21:23:11 -07:00

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// Copyright (c) 2010, Lawrence Livermore National Security, LLC. Produced at
// the Lawrence Livermore National Laboratory. LLNL-CODE-443211. All Rights
// reserved. See file COPYRIGHT for details.
//
// This file is part of the MFEM library. For more information and source code
// availability see http://mfem.org.
//
// MFEM is free software; you can redistribute it and/or modify it under the
// terms of the GNU Lesser General Public License (as published by the Free
// Software Foundation) version 2.1 dated February 1999.
// Implementations of classes FABilinearFormExtension, EABilinearFormExtension,
// PABilinearFormExtension and MFBilinearFormExtension.
#include "../general/forall.hpp"
#include "bilinearform.hpp"
namespace mfem
{
BilinearFormExtension::BilinearFormExtension(BilinearForm *form)
: Operator(form->Size()), a(form)
{
// empty
}
const Operator *BilinearFormExtension::GetProlongation() const
{
return a->GetProlongation();
}
const Operator *BilinearFormExtension::GetRestriction() const
{
return a->GetRestriction();
}
// Data and methods for partially-assembled bilinear forms
PABilinearFormExtension::PABilinearFormExtension(BilinearForm *form)
: BilinearFormExtension(form),
trialFes(a->FESpace()), testFes(a->FESpace())
{
elem_restrict_lex = trialFes->GetElementRestriction(
ElementDofOrdering::LEXICOGRAPHIC);
if (elem_restrict_lex)
{
localX.SetSize(elem_restrict_lex->Height(), Device::GetMemoryType());
localY.SetSize(elem_restrict_lex->Height(), Device::GetMemoryType());
localY.UseDevice(true); // ensure 'localY = 0.0' is done on device
}
}
void PABilinearFormExtension::Assemble()
{
Array<BilinearFormIntegrator*> &integrators = *a->GetDBFI();
const int integratorCount = integrators.Size();
for (int i = 0; i < integratorCount; ++i)
{
integrators[i]->AssemblePA(*a->FESpace());
}
}
void PABilinearFormExtension::Update()
{
FiniteElementSpace *fes = a->FESpace();
height = width = fes->GetVSize();
trialFes = fes;
testFes = fes;
elem_restrict_lex = trialFes->GetElementRestriction(
ElementDofOrdering::LEXICOGRAPHIC);
if (elem_restrict_lex)
{
localX.SetSize(elem_restrict_lex->Height());
localY.SetSize(elem_restrict_lex->Height());
}
}
void PABilinearFormExtension::FormSystemMatrix(const Array<int> &ess_tdof_list,
OperatorHandle &A)
{
const Operator* trialP = trialFes->GetProlongationMatrix();
const Operator* testP = testFes->GetProlongationMatrix();
Operator *rap = this;
if (trialP) { rap = new RAPOperator(*testP, *this, *trialP); }
const bool own_A = (rap!=this);
A.Reset(new ConstrainedOperator(rap, ess_tdof_list, own_A));
}
void PABilinearFormExtension::FormLinearSystem(const Array<int> &ess_tdof_list,
Vector &x, Vector &b,
OperatorHandle &A,
Vector &X, Vector &B,
int copy_interior)
{
Operator *oper;
Operator::FormLinearSystem(ess_tdof_list, x, b, oper, X, B, copy_interior);
A.Reset(oper); // A will own oper
}
void PABilinearFormExtension::Mult(const Vector &x, Vector &y) const
{
Array<BilinearFormIntegrator*> &integrators = *a->GetDBFI();
const int iSz = integrators.Size();
if (elem_restrict_lex)
{
elem_restrict_lex->Mult(x, localX);
localY = 0.0;
for (int i = 0; i < iSz; ++i)
{
integrators[i]->AddMultPA(localX, localY);
}
elem_restrict_lex->MultTranspose(localY, y);
}
else
{
y.UseDevice(true); // typically this is a large vector, so store on device
y = 0.0;
for (int i = 0; i < iSz; ++i)
{
integrators[i]->AddMultPA(x, y);
}
}
}
void PABilinearFormExtension::MultTranspose(const Vector &x, Vector &y) const
{
Array<BilinearFormIntegrator*> &integrators = *a->GetDBFI();
const int iSz = integrators.Size();
if (elem_restrict_lex)
{
elem_restrict_lex->Mult(x, localX);
localY = 0.0;
for (int i = 0; i < iSz; ++i)
{
integrators[i]->AddMultTransposePA(localX, localY);
}
elem_restrict_lex->MultTranspose(localY, y);
}
else
{
y.UseDevice(true);
y = 0.0;
for (int i = 0; i < iSz; ++i)
{
integrators[i]->AddMultTransposePA(x, y);
}
}
}
} // namespace mfem